Starting device for mercury-lamps.



PATENTED APR- 28, 1908. G. P. STEINMETZ.

STARTING DEVICE FOR MEROURY'LAMPS. I

APPLICATION TILED 0OT.17, 1904.

Witn es ses I IhVentor Charles P. Steinmetz,

vts PATENT ornron. A

\ l CHARLES P. STEINMETZ, OF SOHENEOTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

Specification of Letters Patent.

Patented April 28, 1908.

Application filed October 17, 1904. Serial No. 228,661.

ing mercury arc lamps or similar apparatus and is particularly applicable to lamps of the type in which a solenoid operates a plunger or other movable member to start the arc.

The invention will be more readily understood by reference to the following description taken in connection with the drawing forming a part of this specification.

In the figure the conductors1,1 represent the distributing mains of the constant pressure circuit supplying current to a mercury vapor tube 2 of ordinary construction which may be operated in parallel with suitable translating devices such for instance, as the vapor lamps 10 and 11. 'The' complete mercury lamp comprises the upper electrode 3, the mercury electrode 4, thezstarting filament 5 of suitable resistance material, the solenoid 7 and a magnetic plunger 6 floating on the mercury and carrying in a cup-shaped depression in its top a small quantity of mercury which makes contact with the lower end of the filament 5. When the lamp is startedthe current in solenoid 7 draws down the plunger 6 and opens the circuit through filament 5 thus forming a spark at the end of the filament and starting the mercury vapor are. The starting filament 5 is preferably of very high resistance so that under normal conditions of working, practically all of the current passing through the lamp will be carried by the mercury arc. As the consequence of this high resistance the starting current in solenoid 7 is relatively small. Considerable difficulty has been en- 4 countered in making the solenoid 7 sufficiently powerful to operate the plunger 6 without unduly increasing its resistance and hence its heat loss under normal conditions of working. To overcome these difficulties I provide a resistance 8 in parallel with the starting filament 5, but in series with the solenoid 7 so that at the instant of starting the current passing through solenoid 7, consists not only of the current in the starting filament, but also of'the current through the resistance 8. An automatic circuit breaker 9 of ordinary form has its coil connected in series with the lamp tube so that when the current in the lamp has reached substantially its normal value thearmature 9 of the circuit breaker will automatically open the circuit through resistance 8 and will keep the circuit open so long as normal current flows through the lamp.

While the arrangement above described for abnormally increasin the effectiveness of the solenoid during the interval of starting is believed to be the preferable arrangement it is obvious that other modifications might be used to roduce a similar result and I do not wish to imit my invention to the specific details described above. Such a modification is illustrated in connection with lamp 10, the solenoid 12 of which is composed of two separate windings 13 and 14. Winding 13 is connected directly iii series with the vapor tube whereas winding 14 is energized by current received from the main 1 through a cut-out 15 and resistance 16, and hence derives its current through a path independent of the vapor carrying tube. Another form of supplemental means for energizing the solenoid or electro-magnet during the starting operation is shown in connection with lamp 11, and differs from that shown in connection with lamp 10 by having one of the coils 17 of the solenoid ener ized by current from a bat tery 18 instead 0% by current from the mains 1 and 1. These and similar'modifications I desire to include within the scope of the annexed claims.

By my improved construction I am able to use a solenoid of com aratively few turns, and to insure great re iability in the operation of the plunger 6, thereby materially improving the operation of lamps of the type illustrated.

My present application is directed to certain improvements in va or electric devices and systems of the genera type shown in my application, Serial No. 185,790, electric lamp, filed December 19, 1903. In my said earlier application claims are made broadly on the vapor lamp of the lunger ty e and on other features and details herein s own. I

am not herein attem ting to claim anything that could be claim tion.

What I claim as new and desire to secure by Letters Patent of the United States, is:

in said earlier applica- 1. In an electrical system, the combination when the current in said vapor tube has atof a vapor electric device having an initially conductive path of high resistance therein, means for sup lying current therethrough, a movable mem er to start an arc in said device, electro-magnetic means traversed by said current and disposed for operating said movable member, and means for abnormally increasing the effectiveness of said electromagnetic means at starting.

2. In an electric'algsystem, the combination of a mercury arc tube, means for supplying current thereto to form an arc,-a movable member to start said arc, 'electro-magnetic means traversed by all the current flowing through said tube and disposed for operating said movable member, and means for abnormally increasing the ampere turns of said solenoid during the interval of starting.

3. In an electrical system the combination of a mercury vapor tube, means for supplying current thereto, a movable member within said tube, a solenoid for operating said movable member, and an auxiliary conducting path for supplying current to said solenoid independent of that transmitted by said vapor tube.

4:. In an electrical system, the combina tion of a mercury vapor tube, means for supplying current thereto, a movable member within said tube, a solenoid for operating said movable member, an auxiliary conductive path for supplying current to said solenoid independent of that transmitted by said vapor tube, and means for automatically opening said auxiliary path when the current in said vapor tube has attained substantially its normal value. 1

5. In an electrical system, the combination of a mercury vapor tube, a plunger within said tube, a solenoid for operating said plunger, and a resistance device connected in series with said solenoid and receiving current independent of that transmitted by said vapor tube.

6. In an electrical system, the combination of a mercury vapor tube, means for supplying current thereto, a movable plunger within said tube, a solenoid for operating said plunger, a resistance device connected in series with said solenoid and receiving current independent of that transmitted by said vapor tube, and automatic means for opening the circuit through said resistance device tained substantially its normal value.

7. In an electrical system, the combination of a mercury vapor tube, a movable member within said tube, an electro-magnet normally connected in series with said tube and traversed by the main current thereof, and means for increasing the strength of said electro-magnet at starting to operate said movable member.

8. In an electrical system, the combination of .a vapor electric device, means for supplying current thereto to form an are, a movable member within said tube to start said arc, an electro-magnet for operating said movable member and normally traversed by current from said vaporelectric device, and a path for current in series with said electromagnet and in shunt with said vapor tube.

9. In an electrical system, the combination of a mercury vapor tube, means for supplying current thereto, a movable member within said tube, an electro-magnet for operating said movable member connected in series with said tube, a path for current-in series with said electro-magnet and in shunt with said tube, and means for automatically decreasing the current in said auxiliary path when the current in said vapor tube increases.

10. In an electrical system, a vapor electric device having a high resistance conductor therein, means for supplying current to said device, an electro-magnet receiving current through said high resistance conductor, and a current path independent of said vapor electric device for permitting the passage of additional current to said electromagnet when the device is started.

11. In an electrical system, a vapor electric device having a stationary tube, a high resistance path permitting the passage of current therethrough before an arc is established therein, electroanagnetic means energized by said current for starting an arc in said tube, and supplemental means for energizing said electro-magnetic means at starting.

In witness whereof I have hereunto set my hand this 15th day of October, 1904:.

CHARLES P. STEINMETZ.

Witnesses:

I-IELEN ORFORD, C. C. HOLLISTER. 

